Stockholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended			9 Months Ended		53 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Jun. 30, 2012
Class of Stock [Line Items]
Stock Repurchased and Retired During Period, Shares						0
Treasury Stock, Shares, Acquired	393,031	505,137	182,784	898,168	741,959
Treasury Stock Acquired, Average Cost Per Share	$ 13.49	$ 13.98	$ 14.01	$ 13.76	$ 14.23	$ 15.37
Shares Repurchased to date						5,853,975
2008 Repurchase Program [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount				$ 90,000
2012 Repurchase Program [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount				$ 50,000